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riadik2000 [5.3K]
3 years ago
10

All isotopes of technetium are radioactive, but they have widely varying half-lives. If an 800.0 g sample of technetium-99 decay

s to 100.0 g of technetium-99 in 639 000 y. What is it's half-life?
Mathematics
1 answer:
erica [24]3 years ago
3 0
The formula for A = Ao (1/2) ^ t/h
So sub in.
100 = 800 (1/2) ^ 639,000/?
That's all i can do lol

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Step-by-step explanation:

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